Sludge scoop for oil tankers

ABSTRACT

This invention is directed to apparatus for removing sludge from the bottom of the tanks of an oil tanker and includes a hoisting winch at the top of the tank with its cable extending down into the tank and attached to a sludge scoop initially remotely located at the bottom of the tank. An adjustably positioned snatch block is used to control the lead of the cable and to establish the desired path of travel of the sludge scoop.

United States Patent Modrey Feb. 22, 1972 [54] SLUDGE SCOOP FOR OILTANKERS [72] Inventor: Henry .1. Modrey, Eagle Drive, Stamford,

Conn. 06903 [22] Filed: Sept. 11, 1969 [21] Appl.No.: 857,154

[52] U.S.Cl ..15/246.5, 15/93, 37/135,

172/265, 214/15 C [51] Int. Cl ..B63b 57/00 [58] Field of Search 15/104. 1 6, 104.3, 236, 246.5,

[56] References Cited UNITED STATES PATENTS 493,421 3/1893 Butler..37/136 2,147,663 2/1939 Miller ..37/135 X 2,147,634 2/1939 Campbell..37/135 X FOREIGN PATENTS OR APPLICATIONS 869,885 6/1961 Great Britain..37/135 Primary Examiner-Edward L. Roberts AttorneyI-Iane & Baxley [57] ABSTRACT This invention is directed to apparatus for removing sludgefrom the bottom of the tanks of an oil tanker and includes a hoistingwinch at the top of the tank with its cable extending down into the tankand attached to a sludge scoop initially remotely located at the bottomof the tank. An adjustably positioned snatch block is used to controlthe lead of the cable and to establish the desired path of travel of thesludge scoop.

5 Claims, 15 Drawing Figures BPEQBWZSS flfi E FEB 2 7% SHEET 0F 3INVENTOR.

HENRY J. MODREY Ham M EMZ A-r ra/e/va rs SLUDGE SCOOP FOR OIL TANKERSTHE INVENTION This invention relates generally to new and usefulimprovements in devices for removing sludge from the bottoms of tanksand particularly seeks to provide a novel cable-operated scoop forremoving sludge that accumulates between the fore and aft stringers orribs at the bottoms of oil tanker holds.

For the purposes of this description it is believed sufficient to statethat a typical tank hold is defined by the hull and bottom plating, thedeck plating, the longitudinal bulkhead, and a pair of transversebulkheads. The bottom of the hold is stiffened by a plurality of spacedgenerally parallel longitudinal channels or ribs. Surging of the tankcontents in a seaway is minimized by suitably positioned transverseand/or longitudinal baffles. Access to each hold is generally gainedthrough small circular holes in the deck that are normally closed bycover plates removably bolted thereover.

Crude oil carried within the hold will deposit a sludge on and betweenthe longitudinal channels or ribs that must be removed periodically whenthe hold is empty. Normally, efforts are made to establish and maintaina cleaning cycle such that no more than a few inches of sludge builds upbetween cleanings. The sludge between the stringers is difficult andmessy to remove, and washing alone is generally insufficient for theremoval of sludge deposits. Heretofore, its removal has been effectedmanually by shoveling the sludge into a relatively small capacity bucketand hoisting it out through the deck holes.

However, through the use of this invention sludge removal issubstantially mechanized and the operation may be effected in a muchshorter time and with little or no shovel work, except for possibletrimming.

Therefore, an object of this invention is to provide a cableoperatedscoop for the removal of sludge from the bottoms of oil tankers holds.

Another object of this invention is to provide a removable or foldableholddown handle to hold the mouth of the scoop toward contact with thebottom plates of the hold.

Another object of this invention is to provide a scoop of the characterstated that includes a permanent magnet releasably secured to the bottomof the scoop adjacent the mouth thereof to draw the mouth portiondownwardly toward contact with the bottom plates of the hold.

Another object of this invention is to provide a scoop of the characterstated in which the operating cable therefor is led downwardly from adeck opening and reeved through a quick opening snatch block adjustablypositioned between a selected pair of channels or ribs and then to thebail or bridle of the scoop to which it is releasably connected as by asnaphook.

Another object of this invention is to provide a scoop of the characterstated in which the snatch block is adjustably mounted on a thwartshipbar that is releasably and adjustably clamped to a selected channel orrib.

A further object of this invention is to provide a scoop of thecharacter stated in which the scraper edge at the mouth thereof isangularly adjustable.

A further object of this invention is to provide an auxiliary plow forbreaking up heavy sludge prior to employing the scoop.

A further object of this invention is to provide a sludge removal systemof the character stated in which a holddown handle is provided for theplow.

With these and other objects, the nature of which will be apparent, theinvention will be more fully understood by reference to the drawings,the accompanying detailed description and the appended claims.

In the drawings: 7

FIG. 1 is a fragmentary perspective showing the sludge scoop in positionfor use.

FIG. 2 is a side elevation, partly in section, of one form of scoop.

FIG. 3 is a bottom plan view thereof.

FIG. 4 is an end elevation looking toward the open mouth thereof.

FIG. 5 is an end elevation of the assembly of FIG. 1.

FIG. 6 is a somewhat schematic transverse section of a tanker hold.

FIG. 7 is a side elevation of a modification of the scoop.

FIG. 8 is an end elevation of the modification of FIG. 7 looking towardthe open mouth thereof.

FIG. 9 is an enlarged fragmentary perspective showing the use of theauxiliary plow.

FIG. 10 is a fragmentary side elevation of another modification of thescoop with a pivotable handle.

FIG. 11 is a fragmentary side elevation corresponding with FIG. 10 withthe handle in position for pivoting.

FIG. 12 is a fragmented plan of a modified sheave assembly.

FIG. 13 is a fragmented side elevation of the sheave assembly of FIG.12.

FIG. 14 is a fragmented plan of the sheave assembly of FIG. 12 as thecable is disengaged therefrom.

FIG. 15 is a somewhat schematic representation of the scoop beingemptied.

Referring to the drawings in detail the invention, as illustrated, isembodied in apparatus for removing sludge from the bottoms of oil tankerholds and includes an elongated scoop generally indicated 5 and havingflat bottom 6 and upper body portion 7 of generally circular crosssection. The transverse dimensions of scoop 5 are such that the scoopwill pass freely through a deck hole as will be hereinafter more fullydescribed.

Upper body portion 7 of scoop 5 preferably is constructed fromnonferrous material in order to avoid any possibility of sparks as it ispulled along the iron plates of the hold bottom. The scoop bag ispreferably molded of nitril rubber.

Mouth end of the bottom 6 is configured to define downwardly slantingscraper blade 8 that lifts the sludge from the bottom plates as thescoop is pulled therealong.

Bail 9 is pivotally attached as at 10 to the mouth end of scoop 5 forattachment to hauling cable 11 by means of fastener 12. Sister hooks andother well-known fasteners could be used equally as well as thecoupling, and the bail could be replaced by a wire rope bridle ifdesired. Various other well-known devices could also be employed forattaching scoop 5 to hauling cable 11.

Permanent bar magnet 13, having short lanyard 14, extends across bottom6 adjacent scraper blade 8 and is slidably supported therein in suitablegrooves formed in the bottom. Although the downward force acting onblade 8 will tend to hold the mouth of the scoop down as it is pulled bycable 11, the magnet will assist in such action when the scoopapproaches contact with the plates of the hold.

As seen in FIG. 6, in order to operate scoop 5 mechanically, portablehoist l5 provided with winch 16 containing cable II is moved intoposition over deck hole l7 that opens into the hold selected forcleaning. Scoop 5 is then connected to the cable and lowered to thebottom of the hold where a previ ously stationed crewmember will bodilymove it to a position adjacent transverse surge baffle 18 andintermediate a pair of channels or ribs 19,19.

As seen in FIGS. 1 and 5, cable 11 is then reeved through the pulley orsheave 20 of an open snatch block 211 having a securing latch 22, andthe snatch block is then closed and hoist 15 is then operated to haulscoop 5 along the path established by the location of the snatch block.In the embodiment of FIG. 1, as bail 9 of the scoop approaches thesnatch block, the crewmember releases latch 22 thereof to permit theblock to open and cause the cable to disengage from pulley 20 so thatscoop 5 will be lifted upwardly to and through hole 17. As the scoopcommences its upward movement, the crewmember will remove magnet 13 sothat the scoop will not be attracted to and hang up against the metalsurrounding the manhole.

This cycle of operations is repeated until all of the sludge in thatparticular path of scoop travel has been removed, after which snatchblock 21 must be repositioned to clear the sludge from an adjacent path.

It should be mentioned that since the spacing between ribs 19 isgenerally on the order of 36 inches and that scoop 5 must be narrowenough to clear the l6-inch-diameter deck hole, it will require threepaths of haul between each pair of ribs to remove all of the sludgetherebetween. Accordingly, means must be provided for repositioning thesnatch block after each path has been cleared.

Toward this objective (see FIGS. 1 and 5) snatch block 21 is providedwith clamp 23 that adjustably secures it to transverse bar 24 thatcarries a pair of adjustable clamp arms 25,25 and clamp crank 26 forreleasably clamping bar 24 onto a rib 19. When clamp arms are releasedthey may be moved to any desired position along bar 24, thus determiningthe direction and length of extension of the bar relative to supportingrib l9, and clamp 23 of snatch block 21 may be moved to and secured atany desired position along the extended portion of bar 24 to establish anew position of the snatch block and a new path of travel for the scoop.

Preferably, snatch block 21 should be swivel connected to its clamp 23in order to permit sheave 20 always to lie in the same plane as thatdefined by the two arms of hauling cable 11 as that plane changes inangle when the snatch block is moved step by step away from verticalalignment with manhole 17, otherwise the cable would tend to jump sheave20 or at least cause the sheave to bind against the sideplates of thesnatch block. Also, the diameter of sheave 20 should be such that whensnatch block 21 is secured in its operating position on bar 24, thelower rim of the sheave will be at least as low or lower than pivots 10of ball 9 so that there will be no upward pull on the scoop as it ishauled along the bottom of the hold.

In the modification shown in FIGS. 7 and 8 of the drawings a sludgescoop generally indicated 27 includes a nonferrous metallic tubularfront section 28 having a mesh-covered rubber bag 29v secured to itsrear end. A scraper blade supporting frame 30 is pivotally attached tothe lower front portion of front section 28 as at 31 and an edgedscraper blade 32 is removably secured to the forwardly projectingportion of frame 30 by screws 33. One arm of frame 30 is provided with aspring-loaded locking pin 34 adapted to engage in a selected detent hole35 to change the angle of setting of blade 32.

In normal scraping operation blade 32 extends beyond the periphery offront section 28 and thus would not clear the deck manhole when thescoop is hoisted therethrough. Accordingly, when hauling cable 11 isdisengaged from the snatch block, locking pin 34 is moved to the lowerdetent hole 35 to swing blade 32 to a position entirely within theperiphery of front section 28. In this position the blade edge will beat the line E of FIG. 8.

Front section 28 is provided with slanted socket 36 to receive removablehandle 37 that a member of the cleaning crew can use to hold down thefront end of the scoop in case the blade does not properly bite into thesludge. The handle is pulled from its socket before the scoop starts onits vertical ascent towards the deck hole.

The usual pivoted bail 38 is provided for connection with the haulingcable.

It sometimes occurs that with certain types of crude oils, or whencleaning has become overdue, the sludge becomes overly thick and dense.Under such conditions it is preferable to first break up the sludgebefore scooping it out.

To this end, and as shown in FIG. 9, a plow 39 having a foldableholddown handle 40, is attached to hauling cable 11 and is pulledthrough the caked sludge in as many passes as are required to break itup, after which handle 40 is folded and the plow removed through thedeck hole. Such a plowing operation generally will require the servicesof two workers, one on each end of handle 40.

The embodiment depicted in FIGS. 10 and 11 includes a foldable orpivotable handle 50 which comprises fork 51 and extension 52. Two slots53 engage two posts 54 on section 55 of scoop 56. Two lugs 57 formed onsection 55 prevent counterclockwise movement of handle 50 as seen inFIG. 10. In order to move handle 50 to its collapsed or folded position,it is pulled upward whence it is free to rotate (see FIG. 11) with fork51 clearing section 55. A clamp or hook 58 engages cable 1 1 to securehandle 50 within the front section of the scoop so that it will clearwithin the limiting area of hole 17 in the deck.

FIGS. 12, 13 and 14 present an alternate snatch block arrangement.Sheave 60 comprises a stationary sideplate 61 and a movable sideplate62. Sideplate 61 has post 63 supporting pulley 64 for cable 11. Thispulley is cast with a multiplicity of runoff grooves 65 on its sideadjacent sideplate 62. Sideplate 61 is provided with wedge-shaped cam 66and sideplate 62, pivotable about pin 67 has hinge pin 68 carryingintegral hook 69 and cam 70 biased counterclockwise as seen in FIG. 13by spring 71. Accordingly, as seen in FIG. 12, hook 69 engages sideplate61. To release cable 11 from this snatch block assembly a cone-shapedactuator 72 is formed by pieces 73, 74 clamped on to cable 11 by bolts75. As shown in FIG. 14, cam 70 trips open first as cam 66 starts tobias cable 11 toward the open sideplate 62. With continued cam actioncable 11 is caught in runoff groove 65 and the cable is freed forhauling up the scoop. The many runoff grooves are useful to cut down thecable travel between cam action and groove engagement. Cam 70 may alsocarry a handle for manual operation of the released mechanism.

In the embodiment shown in FIG. 15, post 10 for bail 9 has been moveddown close to the center of gravity 75 of the loaded scoop. Thus themoment arm 76 is made small (compared to the previous figured location)for either manual or mechanical means to empty the scoop into container77 for appropriate disposal.

I claim:

1. Apparatus for removing sludge from the bottom of a tank including, ahoisting winch located at the top of said tank and provided with ahauling cable extending at least to the bottom of said tank, a sludgescoop adapted to be positioned initially. at the bottom of said tank ata location remote from the vertical from said hoisting winch, holdingmeans receiving said cable from said winch for connecting said cable tosaid sludge scoop, means for attaching said cable to said sludge scoop,and

forcing means for forcing the mouth of said sludge scoop towards contactwith the bottom of said tank, said forcing means including a holddownhandle affixed to said sludge scoop adjacent the mouth thereof, andpivot means for pivoting said handle into the profile of said mouth toreduce the clearance required by said sludge scoop for hoisting the sameout of the tank.

2. The apparatus according to claim 1 wherein said pivot means comprisea pivot pin secured to the scoop and protruding from a lateral wallthereof, said holddown handle including a slot, said pivot pin being inslidable engagement with said slot for pivoting the handle about saidpin between a hoist position in which the handle is located within theprofile of the scoop mouth and a working position in which the handleprotrudes upwardly from the scoop.

3. The apparatus according to claim 1 wherein said holddown handlecomprises a bar having a grip at one end and being bifurcated at itsother end, the branches of said bifurcated bar end straddling oppositesides of said scoop, each of the branches including a lengthwise slot, apivot pin protruding from each of said scoop sides into slidable andpivotal engagement with the respective slot for pivoting the handleabout said pins between a hoist position in which the handle is locatedwithin the profile of the scoop mouth and a working position in whichthe handle protrudes upwardly from the scoop.

4. The apparatus according to claim 3 and comprising a stop means oneach of said sides of the scoop, each of said stop means being disposedrelative to the respective pivot pin so as to arrest the handle in theworking position and to block pivoting of the handle into the hoistposition, axial lifting of the handle a predetermined distance in saidworking position freeing the handle from the stop means for pivoting ofthe handle into the hoist position.

5. The apparatus according to claim 4 wherein each of said stop meanscomprises a lug protruding from the respective side of the scoop, eachof said lugs being disposed to engage the respective branch of the barwhen the handle is in its working position and being clear of saidbranch when the handle is axially lifted said predetermined distancethereby freeing the handle for pivoting into the profile of the mouth ofthe scoop.

1. Apparatus for removing sludge from the bottom of a tank including, ahoisting winch located at the top of said tank and provided with ahauling cable extending at least to the bottom of said tank, a sludgescoop adapted to be positioned initially at the bottom of said tank at alocation remote from the vertical from said hoisting winch, holdingmeans receiving said cable from said winch for connecting said cable tosaid sludge scoop, means for attaching said cable to said sludge scoop,and forcing means for forcing the mouth of said sludge scoop towardscontact with the bottom of said tank, said forcing means including aholddown handle affixed to said sludge scoop adjacent the mouth thereof,and pivot means for pivoting said handle into the profile of said mouthto reduce the clearance required by said sludge scoop for hoisting thesame out of the tank.
 2. The apparatus according to claim 1 wherein saidpivot means comprise a pivot pin secured to the scoop and protrudingfrom a lateral wall thereof, said holddown handle including a slot, saidpivot pin being in slidable engagement with said slot for pivoting thehandle about said pin between a hoist position in which the handle islocated within the profile of the scoop mouth and a working position inwhich the handle protrudes upwardly from the scoop.
 3. The apparatusaccording to claim 1 wherein said holddown handle comprises a bar havinga grip at one end and being bifurcated at its other end, the branches ofsaid bifurcated bar end straddling opposite sides of said scoop, each ofthe branches including a lengthwise slot, a pivot pin protruding fromeach of said scoop sides into slidable and pivotal engagement with therespective slot for pivoting the handle about said pins between a hoistposition in which the handle is located within the profile of the scoopmouth and a working position in which the handle protrudes upwardly fromthe scoop.
 4. The apparatus according to claim 3 and comprising a stopmeans on each of said sides of the scoop, each of said stop means beingdisposed relative to the respective pivot pin so as to arrest the handlein the working position and to block pivoting of the handle into thehoist position, axial lifting of the handle a predetermined distance insaid working position freeing the handle from the stop means forpivoting of the handle into the hoist position.
 5. The apparatusaccording to claim 4 wherein each of said stop means comprises a lugprotruding from the respective side of the scoop, each of said lugsbeing disposed to engage the respective branch of the bar when thehandle is in its working position and being clear of said branch whenthe handle is axially lifted said predetermined distance thereby freeingthe handle for pivoting into the profile of the mouth of the scoop.